Even at 300
feet long, the Chinese Treasure Fleet lacked the manuverability of the smaller
vessels Portuguese shipbuilders successfully pioneered in the fifteenth century.
Dutch, French, and English copied these swifter, smaller vessels and improved
upon them. Magellan's circumnavigation of the globe relied upon these smaller
vessels as well.

2. In 1421
Chinese sailors lacked experience in the Southern Hemisphere oceans where
winds and currents flow counterclockwise (opposite direction from the Northern Hemisphere where they flow clockwise).
Their southern hemispheric experience was limited to coastal trading along
the coasts of what are now Indonesian islands and the northeastern coast of
Africa.

3. Many professionals
in the fields he covers do not think he has sufficient evidence for his claims.
See a collection of references on-line.

4. Europeans
did in fact map the Atlantic and elsewhere without Chinese help. The Cantino
map is a well-documented copy of a Portuguese chart made in the second
half of the year 1502. The Duc d'Este authorized a substantial reward to a
cartographer willing to copy the Portuguese map. Copies of his instructions
remain in the archives of his palace.